unit-testing - 单元测试 Java 8 谓词

Question

我有一个这样的 Java 8 谓词。我如何为此编写单元测试

 Predicate<DTO> isDone = (dtO) ->
                (!dto.isFinished() &&
                !dto.isCompleted());

谢谢

Answer 1

我会这样测试它:

private final Predicate<DTO> isDone = (dto) ->
        (!dto.isFinished() && !dto.isCompleted());

@Test
public void a() throws Exception {
    // given
    DTO dto = new DTO(true, true);

    // when
    boolean result = isDone.test(dto);

    // then
    assertThat(result).isFalse();
}

@Test
public void s() throws Exception {
    // given
    DTO dto = new DTO(true, false);

    // when
    boolean result = isDone.test(dto);

    // then
    assertThat(result).isFalse();
}

@Test
public void d() throws Exception {
    // given
    DTO dto = new DTO(false, true);

    // when
    boolean result = isDone.test(dto);

    // then
    assertThat(result).isFalse();
}

@Test
public void f() throws Exception {
    // given
    DTO dto = new DTO(false, false);

    // when
    boolean result = isDone.test(dto);

    // then
    assertThat(result).isTrue();
}

@AllArgsConstructor
public static class DTO {
    private final boolean isFinished;
    private final boolean isCompleted;

    public boolean isFinished() {
        return isFinished;
    }

    public boolean isCompleted() {
        return isCompleted;
    }
}

代替 a、s 和 f 正确命名测试，如:should_be_done_when_it_is_both_finished_and_completed。

我想 DTO 只是一个值对象，所以我宁愿创建真实实例而不是使用模拟。